Crocus are among the first flowers I planted when first planting my own garden, at age twenty.
I had long loved the early spring crocus in my mother’s garden, lining the walk leading to the entry door, and at the front of her perennial borders surrounding the backyard. Early crocus were among the small bulbs more ambitiously planted when I made a little rock garden in the front yard of the first home my husband and I owned. Specie tulips and miniature daffodils along with diminutive plantings of creeping campanula (poscharskyana), moss phlox, johnny jump-ups, small dianthus, all found a home in that garden.
It was a small viewing garden, inside the restricted space of a city plot, which gave me and passersby much enjoyment; and the crocus were the introit to the garden growing season.
Because of their very early appearance in spring, they are eagerly looked for each year. The ease with which the Dutch imported corms may be grown makes them favorites for gardeners of all levels of experience.
The time to purchase these bulbs is early fall, and it is best to get them into the ground as quickly as is practical, but they will survive and grow if you delay. Theoretically you can plant until the frosts harden the ground.
A page for general instructions on planting your bulbs, and descriptions of the minor bulbs is one of the earliest of my garden pages, find out about Small Bulbs.
Click here for more on Small Bulbs
Through the years I found that stands of bulbs will grow very well in clay, but once rodents find their location the stands of these flowering bulbs will diminish as mice and squirrels voraciously feast on them over the winter. If there is deep snow cover even more of the bulbs will be gone.
I came across an extremely well done book that covers everything most gardeners would like to know about planting crocus, and it included some very helpful tips. It holds a great deal of information for those who might wish to specialize in growing crocus and collect many types. It is surprising how many species of crocus there are, and what a wide range of habitats they have come to adapt to.
One of these is the idea that no matter how few crocus bulbs you have, even if only two, divide them into two stands in different locations to try to outwit the animals who might locate and eat your bulbs. We usually plant many more corms (the proper term for the storage portion) than two since they are sold in bags of fifteen or more in most places, but the hint to make more than one area of spring crocus is certainly well taken, I believe.
The book that is so helpful, and to which I will occasionally refer because it is so expert and detailed about specific types, is called ‘Crocuses: A Complete Guide to the Genus‘. Although the common types of crocus are easy, this information can make a big difference in the longevity, bloom, and health of your crocus planting.
Crocuses: A Complete Guide to the Genus
The Dutch Crocus
These are the garden cultivated crocus we so often associate with the name of this plant. They have the same shape and form, but much larger and showier blooms than the species, which are often lumped together and called “snow crocus” when sold.
The garden crocuses are varied in color from white, to blue-purple, purple, golden yellow, and a striped form, and although I admit that I’ve always had a special place in my heart for the species type, this is the one you want to plant if wishing to make a visual impact from a distance. They bloom more closely in time with the early daffodils, but don’t be fooled by a seller’s picture group of tulips, daffodils, and crocus all blooming at once, the crocus are usually long over before the other, larger spring bloomers begin.
That is part of their charm, so plant them where you will be sure to notice on cold days. Like my old fashioned sidewalk trimming, or in view of a window while looking outdoors from your cozy chair, indoors.
It is with these that the collector in me had so much fun. Yes, the mice have eaten their way through most of them and I will have to replenish my stock, but there are many that have braved the last twenty plus years and still put on a good show. That is money well spent, and many years worth of joyous spring reunions. In my garden it is the C. chrysanthus and the C.tommasinianus that bloom floriferously each year. The delicate “Blue Pearl” was one of my favorites, but I don’t think I have it anymore, although there are a few survivors of some of my named varieties.
Some of the other named types I liked very well are the C. chrysanthus “Ladykiller” which are white with a purple streak up the center of each petal, C. olivieri balansae “Zwanenburg” which is dark golden with a comb-striped dark brownish purple up the center of the petal; C. chrysanthus ‘Gypsy Girl’ looks just the same to me, maybe a lighter gold. One variety called “Tricolor” was beautiful, but I’m not sure if you can even find it anymore, and pure white “nivea” is the white that I think I have. If I purchased assortments (as I did, at times) it is anybody’s guess what the true name is. Many of the snow crocus were purchased as named varieties, since that is the only way to be sure of getting a large number of that type. “Ladykiller” and “Zwanenburg” are still widely sold. There was a “Cream Beauty” which was really lovely, too, a very subtle color- bu it if you find it. A note on the name “Zwanenburg…. there is a different specie etruscus which has that name but is a lovely blue, it would be a shame to get the two mixed up. both are pretty, but your expectations might take an adjustment, not to mention any color harmonies you might have planned.
Planting Tips for Crocus
Crocus like good drainage and although they will perform OK in clay soil, when you give them some sand and a bit of fertilizer like bone meal or bulb tone, they will really show-off at bloomtime.
If you plant the corms deeper they grow bigger and divide more slowly; if you plant a little shallower they divide into smaller sized, but far more numerous baby corms.
Another tidbit I had never read before was the classification of crocus bulbs into types according to their preferred conditions:
Group A which needs hot, dry summers.
Group B tolerating some moisture, but needs a dry resting period.
Group C tolerates summer moisture (these are the most common types for our gardens)
…and two subgroups which must not dry out.
~ specifics found in Ruksan’s “Crocuses, A Complete Guide to the Genus”
All of the types of Crocus that I have found available for my garden fall within the C group, and the others would likely not survive without special care of some sort.
Because the book is so thorough in covering the many species of crocus it revealed the native areas of crocus origination and the conditions in which they grow. The usual way that books describe cultivation is so general that the fact that there are groupings for the crocus species simply doesn’t come up. I think the insights that come from this help gardeners like most of us to grow our plants with better results… or at least know why something might disappear from our plantings.
One of the places that my crocus did thrive exceptionally well was within the bulb boxes that I made in the early garden years, the first year here, in fact. Two wooden boxes of a long rectangular shape, with hardware wire nailed across the bottom to thwart the rodents. It was filled with purchased loam that was loose and dark, enriched with bone meal and then planted with a collection of bulbs, lily tulips in the first layer and Snow crocus, Iris reticulata, scillas, and a few others layered on top. Crocus and Scillas have been happiest, while I decided to move the tulips elsewhere.
You can find Campanula poscharskyana at Oakland Nursery in Columbus, Ohio.